We’ve all heard the story. A young Isaac Newton is sitting beneath an apple tree contemplating about the mysterious universe. Suddenly – boink! – an apple hits him on the head. “Aha!” he shouts. In a flash, he understands that the there is a force that brought the apple crashing towards the ground. But, this classic story that Sir Isaac Newton came up with his law of gravity when an apple fell on his head is fake.
The apple tree is real and the apple incident is presumably true but the popular idea that it fell on his head is not true. What is true is that he was on his mother’s farm and watched an apple fall from a tree on the ground and after that, he began to wonder what forces were at work to cause the apple to fall in that way. He eventually realized that if there is some force which attracts objects towards earth. Then,why the Moon did not similarly fall?
But, so far as we know, he was never hit in the head with an apple.